Development of a hybrid near-field scanning optical chemical probe microscope

The Near-field Scanning Optical Microscope (NSOM) is an innovative new form of microscope, which can be used to obtain both topographic images and local spectroscopic information about surfaces. In this thesis, we discuss the design and development of a hybrid instrument capable of topographic, optical and chemical probe imaging based upon a commercial Atomic Force Microscope. This thesis is divided into several sections. We first present a feasibility study, in which several possible optical configurations for the optical components instrument are reviewed. On the basis of this study, we describe in detail the implementation of two different configurations for the microscope: a dark-field illumination and far-field illumination/near-field transmission collection scheme. In the next part of the thesis, we present experiments in which we have developed a novel fibre optic probe that can be used as a combined optical, topographic and chemical force probe. A systematic approach for the development and characterisation of such probes is described including tip geometry and surface roughness, cantilever sensitivity and optical throughput. Finally, the functionality of the microscope is demonstrated by taking combined optical and topographic images of well-defined standard samples. The performance and capabilities of the final instrument are discussed and suggestions for future improvements to the setup are made.